Schools and homes are two of the most critical channels for cancer prevention. This project will test the efficacy of stage-matched, proactive, interactive, and individualized interventions delivered through multiple channels (school and home) to two populations (adolescents and parents) on multiple cancer risks (high fat and low fiber diets, smoking, and ultraviolet light exposure). This experimental intervention trial employs 2 (standard health education v. stage-matched computerized and classroom curriculum) X 2 (home-based expert system intervention v. control) X 4 (yearly repeated measures) design. Schools are randomly assigned to standard v. stage-matched curricula and parents who are the primary food preparers are randomly assigned within schools to home intervention or control conditions. Ninth graders in the school intervention will receive over two years a series of eight individualized computer sessions and four social influence-based classroom sessions. Over two years, parents will receive a series of four computer-generated individualized reports along with self-help manuals, designed to facilitate progress through stages of change for each of the parent's relevant risk factors. The four randomized conditions will permit assessments of the impact on students of the innovative school interventions while assessing the effects on parents of the home-based intervention. We will also assess among students in the school-based program the additive effects of a home-based program for their parents and among parents in the home-based program the additive effects of a school- based program for their teenage children. Since over 80% of eligible students and parents are likely to participate, these programs have considerable potential to dramatically increase impacts on three of the most important behavioral risks for cancer.